The Lausanne-based Dalle Molle Institute for Perceptual Artificial Intelligence said it is 95-per-cent certain the tape does not feature the voice of the long-absent terrorist leader.

The review of the tape was commissioned by France-2 television and its findings were presented by the institute's Professor Herve Boulard in a special TV report shown late Thursday.

He said the institute compared the voice on the tape, first aired two weeks ago on Al-Jazeera, an Arabic television network, with some 20 earlier recordings of bin laden.

U.S. experts maintain the tape will likely never be fully authenticated because its poor quality defies complete analysis by even the most sophisticated voice-print technology.

But U.S. experts who have heard it generally support the conclusion by U.S. law-enforcement officials that it probably is bin Laden speaking.

In the tape, the speaker refers to recent terrorist strikes U.S. officials believe are connected to bin Laden's Al Qaeda network. If fully verified, it would provide the first evidence in a year that bin Laden survived U.S. bombing in Afghanistan.